Play games
Choose the game that interests you and play itfor free.
Complete the quests
Every game has some quests for which you will receive Soul Gems.
Receive rewards
You can exchange your Soul Gems for Steam Wallet top-ups, game keys, CS:GO Skins and other rewards.
I started play today to earn some SG. Then i just.. couldn't stop. It's like a really good game. So i recommend you guys to try it. The launcher is like 10GB so doesn't take long to download. Comment what your opinion about the game.